We'll go now to the world's newest nation, South Sudan. With considerable help from the United States, it split from its northern neighbor Sudan two years ago, gaining independence after decades of civil war that left millions dead. There are now fears that war is returning. Several hundred people are reported killed in two days of factional fighting in the new nation. The conflict appears to have been caused by a split between supporters of the president and the vice president he fired a few months ago.

We go now Andrew Green. He's a journalist working in the capital, Juba. Mr. Green, thank you for joining us.

ANDREW GREEN: Thank you for having me.

WERTHEIMER: Now, what has the situation been like there the last few days? We're hearing about thousands of displaced people in the capital, use of heavy artillery.

GREEN: Yes, over the past few days, there's been heavy gunfire and regular explosions. Calm returned to Juba this morning after another night of sporadic gunfire, and we're waiting to see if that will hold. However, at the same time, there have been reports - I spoke to the deputy governor of neighboring Jonglei State, who says that fighting has broken out in two army barracks there in the east of the country. The president is from the majority Dinka tribe. In the former vice president is from the large Nuer tribe.

Right now, it's too early to say whether the fighting has broken down along ethnic lines. But there are serious concerns that the political divisions could - if the fighting is prolonged, could then lead to fighting along ethnic divisions in the country.

WERTHEIMER: And the displaced persons, what about people being forced out of their homes? What are they doing?

GREEN: Yes, there are reports that more than 20,000 people across Juba have been displaced from their houses, and have been looking for refuge either at the two U.N. compounds here in the city, or at churches and mosques also within the city. This morning, there were - as I was walking around Juba, it was clear that some people were starting to return to their homes to see what was left, if their belongs had been destroyed, but still getting reports from the U.N. that thousands and thousands of people are still hiding out at the two compounds and waiting to see what happens.

WERTHEIMER: Now, could you tell us some of the background of South Sudan? This is a country which was regarded as having lots of potential, right?

GREEN: Indeed, and they have vast natural resources, specifically oil. And it had really been on an upward trajectory since achieving independence in July 2011. However, there's been growing tension within the ruling Sudan People's Liberation Movement Party that led the president, Salva Kiir, to fire his entire Cabinet, including Vice President Reik Machar, who's also extraordinarily popular in his own right, and potentially has created the tensions that led to the recent fighting.

WERTHEIMER: Now, the creation of this country was part of a major push by the United States and other Western nations. Now we're hearing that the U.S. is taking some of its diplomats out of South Sudan. Is help from the outside going to be able to hold the country together?

GREEN: Well, I'm hearing the same thing that the both the U.S. and the EU are evacuating nonessential staff and civilians. U.N. officials have repeatedly said that they're committed to continuing to provide assistance and humanitarian aid to the country. And I think that the United States - and others who have committed so much in terms of resources - will also be committed to seeing out what happens, to helping make sure that peace comes back to the country; and to working with the local political leaders to bring some stability back.

WERTHEIMER: Thank you very much.

GREEN: Thank you, too.

WERTHEIMER: That was journalist Andrew Green, reporting from Juba, in South Sudan. Transcript provided by NPR, Copyright NPR.